The present invention relates to a suspension for a head assembly of a magnetic disk drive unit and a head assembly having the suspension.
A plan view of a magnetic disk drive unit is shown in FIG. 5. The magnetic disk drive unit 100 has a housing 102 in which a magnetic disk 104 and an actuator 106 for positioning a magnetic head are assembled. An arm 108 is actuated by the actuator 106. A suspension 110 is provided to a front end of the arm 108. There is provided a slider 112, which has the magnetic head in a bottom face facing the magnetic disk 104, at a front end of the suspension 110. A head assembly comprises: the arm 108; the suspension 110 fixed to the arm 108; and the slider 112 mounted on the suspension 110.
In FIG. 6, the suspension 110 is fixed to the arm 108, and the slider 112 is mounted on the suspension 110. A gimbal section 114, on which the slider 112 is mounted, is formed at a front free end of the suspension 110. There are formed a plurality of terminals 116, which will be electrically connected to terminals of the slider 112, in the gimbal section 114. A cable pattern 118 is formed on a surface of the suspension 110 and insulated therefrom by an insulating layer. The cable pattern 118 electrically connects terminals 120, which are formed in a base end part of the suspension 110, to the terminals 116. The terminals 120 are formed in an outer face of a terminal section 111, which is formed into an L-shape by bending a part of a base member of the suspension 110. A flexible printed circuit is connected to the terminals 120, so that a control circuit of the magnetic disk drive unit can be electrically connected to the slider 112.
These days, in steps of assembling the head assembly, magnetic heads are apt to be damaged by static electricity. Recently, recording density of magnetic disks are higher, so magnetic heads must be smaller and structures of sliders must be complex. Therefore, the magnetic heads are apt to be easily damaged by the static electricity. Several years ago, resisting voltage of the magnetic heads against the static electricity were about 20-50 V; these days, the resisting voltage thereof is 5 V or less. In the conventional steps of assembling the head assembly, charging the static electricity was restricted by improving factory environment. However, it is impossible to limit the static electricity to 5 V or less by improving the factory environment.
An object of the present invention is to provide a suspension for a head assembly capable of securely limiting the small static electricity, which cannot be limited by improving the factory environment. Even if the resisting voltage of a magnetic head is about 5 V, damaging the magnetic head by the static electricity can be prevented by the suspension.
Another object of the present invention is to provide a suspension for a head assembly capable of easily assembling the head assembly and improving manufacturing yield.
Further object of the present invention is to provide a head assembly having the suspension.
To achieve the objects, the present invention has following structures.
Namely, a basic structure of the suspension of the present invention comprises: a gimbal section being provided to a front end of the suspension and capable of holding a slider; a terminal section being provided to a base end of the suspension and electrically connected to an electric circuit of a magnetic disk drive unit; a plurality of terminals being formed in the terminal section, the terminals being connected to a cable pattern, which will be connected to the slider; and a short pattern being formed in an edge part of the terminal section, one end of the short pattern being connected to a first terminal of the terminals, wherein the edge part of the terminal section is bent so as to elastically make the other end of the short pattern contact a second terminal of the terminals, and a slit is formed in the terminal section, whereby the second terminal is capable of leaving from the short pattern.
In the suspension, the short pattern, the cable pattern and the terminals may be made by etching an electrically conductive layer, which is formed on and electrically insulated from a base member of the suspension.
In the suspension, four terminals, which will be electrically connected to the slider, may be formed in the terminal section, two of the four terminals may be provided on an inner side, and the other two may be provided on an outer side, the short patterns for respectively connecting the inner terminals to the outer terminals may be formed in the terminal section, and the edge part of the terminal section may be bent so as to respectively connect the inner terminals to the outer terminals.
Another basic structure of the suspension of the present invention comprises: a gimbal section being provided to a front end of the suspension and capable of holding a slider; a terminal section being provided to a base end of the suspension and electrically connected to an electric circuit of a magnetic disk drive unit; a plurality of terminals being formed in the terminal section, the terminals being connected to a cable pattern, which will be connected to the slider; and a short pattern being formed in an edge part of the terminal section, one end of the short pattern being connected to a first terminal of the terminals, wherein a slit is formed in the terminal section, whereby the edge part of the terminal section can be bent and a second terminal of the terminals is capable of leaving from the short pattern.
The head assembly of the present invention comprises: the above described suspension; and a slider being held by the gimbal section of the suspension, wherein the cable pattern connects the terminals to the slider, and the cable pattern is formed on and electrically insulated from the base member of the suspension.
In the suspension and the head assembly of the present invention, the magnetic head, which is mounted on the suspension, can be securely protected from the static electricity. The head assembly can be easily assembled without damaging the magnetic head. Therefore, the magnetic head, whose resisting voltage is low and which cannot be treated in the conventional assembling step, can be easily treated, and the yield of manufacturing the head assembly can be improved.
Further, the countermeasure to the static electricity is executed while manufacturing the suspension, so an additional step for preparing the countermeasure to the static electricity is not required.